Plugin update for grails version 6.1.1 and jdk 11

[fernando88to]

Tasks that were done

• This pull request presents a comprehensive refactoring of our plugin's unit tests, with the aim of ensuring full compatibility with the latest version of Grails.

• Plugin update for grails version 6.1.1 and jdk 11

• Create command for create-job

• update documentation

Steps that remain to be taken

• Generate documentation
• Configure application publication

[puneetbehl]

@Richardson-e Could you please review this pull-request?

[dauer]

I ran into an issue with the 2.0.13 version of the Quartz plugin when upgrading from Grails 4.1.1 -> 6.1.1, so I tried building a local version from @fernando88to branch and that fixed my failing tests - so it looks very promising!

Only thing is that when doing a gradle publishToMavenLocal the jar file had -plain added to the filename:
quartz-2.0.14.BUILD-SNAPSHOT-plain.jar
Expecting:
quartz-2.0.14.BUILD-SNAPSHOT.jar

[CLAassistant]

All committers have signed the CLA.

[CLAassistant]

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[puneetbehl]

@matrei Can you please look into this?

[matrei]

@matrei Can you please look into this?

@puneetbehl There is some overlap with #125.
@fernando88to Good with a rewrite of the tests to spock 👍 .
Can you create a new PR based on 3.0.x with only those?

[fernando88to]

@matrei Can you please look into this?

@puneetbehl There is some overlap with #125. @fernando88to Good with a rewrite of the tests to spock 👍 . Can you create a new PR based on 3.0.x with only those?

I am going to do